One hundred and fifty patient participants were recruited to this study, comprising 50 patients on haemodialysis (HD) and peritoneal dialysis (PD) each, and 50 patients with advanced kidney dysfunction (eGFR less than 20mL/ min/1.73m2) undergoing conservative outpatient management (CM). Amongst CM participants, 31 (62%) were in stage 5 of CKD (eGFR consistently below 15mL/min/1.73m2). Baseline characteristics are shown in Table 1 below.
Table 1. Baseline characteristics of participants
|
|
HD
(n = 50)
|
PD
(n = 50)
|
CM
(n = 50)
|
CM stage 5
(n = 31)
|
Age (years)
|
45.5 ± 12.3
|
44.1 ± 11.6
|
59.0 ± 13.5
|
59.9 ± 14.1
|
Sex
|
Male: 23 (46%)
Female: 27 (54%)
|
Male: 25 (50%)
Female: 25 (50%)
|
Male: 27 (54%)
Female: 23 (46%)
|
Male: 14 (45.2%)
Female: 17 (54.8%)
|
Highest level of education
|
None: 2 (4%)
Primary: 6 (12%)
Secondary: 31 (62%)
Tertiary: 11 (22%)
|
None: 1 (2%)
Primary: 5 (10%)
Secondary: 33 (66%)
Tertiary: 11 (22%)
|
None: 2 (4%)
Primary: 10 (20%)
Secondary: 30 (60%)
Tertiary: 8 (16%)
|
None: 1 (3.3%)
Primary: 5 (16.1%)
Secondary: 20 (64.5%)
Tertiary:3 (16.1%)
|
Relationship
status
|
None: 23 (46%)
Partner: 9 (18%)
Married: 14 (28%)
Widowed: 4 (8%)
|
None: 22 (44%)
Partner: 5 (10%)
Married: 19 (38%)
Widowed: 4 (8%)
|
None: 19 (38%)
Partner: 3 (6%)
Married: 21 (42%)
Widowed: 3 (6%)
|
None: 13 (41.9%)
Partner: 2 (6.4%)
Married: 10 (32.3%)
Widowed: 6 (19.4%)
|
Source of income
|
Unemployed: 47 (94%)
Social grant: 37 (74%)
|
Unemployed: 42 (84%)
Social grant: 21 (42%)
|
Unemployed: 38 (76%)
Social grant: 29 (58%)
|
Unemployed: 25 (80.6%)
Social grant: 17 (54.8%)
|
Dialysis vintage (months)
|
47 (15 – 82)
|
24 (13 – 40)
|
-
|
-
|
Comorbidities
|
Diabetic: 11 (22%)
HIV positive: 11 (22%)
CVS disease: 48 (96%)
|
Diabetic: 8 (16%)
HIV positive: 10 (20%)
CVS disease: 43 (86%)
|
Diabetic: 25 (50%)
HIV positive: 11 (22%)
CVS disease: 47 (94%)
|
Diabetic: 14 (45.2%)
HIV positive: 7 (22.6%)
CVS disease: 31 (100%)
|
Hemoglobin (g/dL)
|
9.6 ± 1.6
|
11.1 ± 2.3
|
11.3 ± 2.4
|
10.9 ± 2.4
|
Urea (mmol/L)
|
18.8 ± 8.8
|
22.2 ± 9.7
|
21.7 ± 8.0
|
24.2 ± 8.2
|
Ca (mmol/L)
|
2.24 ± 0.28
|
2.18 ± 0.23
|
2.23 ± 0.24
|
2.19 ± 0.26
|
PO4 (mmol/L)
|
1.89 ± 0.81
|
1.84 ± 0.90
|
1.43 ± 0.56
|
1.54 ± 0.60
|
Albumin (g/L)
|
38.1 ± 6.1
|
33.6 ± 6.8
|
40.2 ± 4.6
|
40.0 ± 4.7
|
Parathyroid hormone (ng/mL)
|
46.6 ± 44.6
|
58.26 ± 40.26
|
15.83 ± 8.82
|
17.99 ± 9.16
|
Significant differences in age (p < 0.001), haemoglobin (Hb) (p < 0.001), phosphate (p = 0.005), albumin (p < 0.001), parathyroid hormone (PTH) (p < 0.001), and prevalence of diabetes mellitus (p = 0.004) were observed between treatment groups; dialysis vintage was greater in patients on HD (p = 0.002). Sex, level of education, relationship status, prevalence of HIV infection and cardiovascular disease, and serum urea and calcium showed no significant difference between groups.
Unemployment was more frequent in the HD treatment group (p = 0.044). Patients on PD were less frequently supported by a social grant than other treatment groups (p = 0.008), whilst patients on HD were more frequent recipients of a social grant than other groups (p = 0.005).
Mean HADS anxiety score was highest in patients on HD (p < 0.001, figure 1, supplementary table 1), a finding which persisted when compared against those CM patients with CKD stage 5 (p = 0.003); anxiety score was lower in patients on PD compared to those on HD (p < 0.001). Patients’ meeting HADS criteria for the presence of anxiety symptoms of significance (score > 4) were significantly more frequent in the HD group (22, 44%) than in the PD (8, 16%) or CM (11, 22%) groups (p = 0.004).
Depression score in patients on HD trended towards being significantly higher compared to other treatment groups (p = 0.083, figure 1). Symptoms of depression (HADS score > 4) were, however, not significantly more frequent in the HD group (17, 34%) than the PD (12, 24%) or CM (11, 22%) groups (p = 0.348).
Composite physical score was better in patients on HD compared to those on PD (p = 0.005), and composite mental score was higher in patients on HD compared to those on PD (p = 0.002) (Figure 2, supplementary table 1).
Subjective assessment of the ability to meet physical activity expectations (role – physical domain) was better in patients on CM compared to those on dialysis modalities (p < 0.001), significance persisted when analysis was restricted to the CM CKD stage 5 group (p = 0.003). Role-physical domain sores were similar between patients on PD and HD (p = 0.574). Patients on PD reported greater physical limitation due to pain than either those on HD (p = 0.030) or those on CM (p = 0.036). Emotional well-being was poorer in HD compared to either the PD (p < 0.001) or CM treatment groups (p < 0.001). Subjective assessment of limitations imposed on meeting emotional roles (role – emotional) appeared to be better in patients on HD compared to those on CM (p = 0.017), however, this positive effect for HD was lost when HD was compared to those patients on CM with stage 5 CKD (p = 0.153). Finally, patients on HD reported being better able to meet their social functioning expectations compared to patients on PD (p = 0.011) but showed no difference in comparison to the CM group (p = 0.288).
Stepwise sigma-restricted multivariate linear regression modelling was used to evaluate the confounding effect of baseline disparities in treatment groups on the scores which showed significant difference between treatment modality (Table 2).
Table 2. Regression analysis: effect of baseline characteristics on HADS and KDQOL-SF36 score
|
|
HADS anxiety
|
HADS depression
|
KDQOL emotional well-being
|
KDQOL social function
|
KDQOL pain
|
Age
|
-0.24 (0.009)*
|
NS
|
NS
|
NS
|
NS
|
Employed
|
NS
|
-0.27 (<0.001)
|
NS
|
NS
|
NS
|
Not on social grant
|
NS
|
NS
|
NS
|
NS
|
NS
|
Diabetes
|
NS
|
NS
|
NS
|
NS
|
NS
|
HD
|
0.21 (0.037)
|
NS
|
-0.71 (<0.001)
|
NS
|
0.26 (0.010)
|
PD
|
-0.27 (0.007)
|
NS
|
0.27 (0.002)
|
-0.34 (0.002)
|
-0.25 (0.007)
|
Dialysis vintage
|
NS
|
NS
|
NS
|
NS
|
|
Hb
|
-0.19 (0.025)
|
-0.19 (0.018)
|
NS
|
NS
|
0.192 (0.023)
|
Phosphate
|
NS
|
NS
|
NS
|
NS
|
-0.19 (0.022)
|
PTH
|
NS
|
NS
|
NS
|
NS
|
NS
|
Albumin
|
NS
|
NS
|
-0.21 (0.006)
|
NS
|
NS
|
*Values are b (p)
|
Younger age and prescription of HD were independently associated with an increased anxiety score, whereas prescription of PD and improving Hb levels reduced anxiety. Treatment modality did not exert an effect on depression, but employment and improving Hb reduced depression levels in respondents in this cohort.
Prescription of haemodialysis reduced emotional wellbeing whilst PD improved emotional well-being when compared to CM; somewhat unexpectedly, albumin level showed inverse effect on emotional well-being. Significant independent effect for dialysis modality was shown for the social function domain, with PD reducing social function relative to CM.
Improving Hb level, control of phosphate, and prescription of HD were found to be independent factors in improving pain score, while prescription of PD resulted in a worsening of pain score relative to CM.